• 한국자동차공학회논문집
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• 제3권5호
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• pp.1-9
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• 1995

The purpose of this study is to develop a computer simulation program for analyzing load transmission characteristics of a helical gear system in design stage. In this analysis, the rotational delay, load distribution, root stress, and contact area are investigated. That is, the influence function of deflection is obtained by finite element analysis and the influence function of approach and gear tooth error are considered. Load distribution, rotational delay, and contact area are calculated by solving load-deflection equation which includes these influence functions and tooth error, and the influence function of the bending moment is obtained by finite element analysis. The root stress is calculated by the load distribution and the influence function of the bending moment. The results of the simulation are cross-checked through a specially designed experimental set-up.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.455-460
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• 2001

Generally, the contribution of curbs and median strip is not considered carefully in analysing and designing the girder bridges. There being curbs, the load given on interior girder relatively reduced and on exterior girder increased. Curbs and median strip reduce the load distribution factor by distributing the load given on girder fairly, In this paper, the Influence of curbs and median strip in wheel distribution through parameter study and lateral distribution test of PSC girder bridge was investigated. Finite-element analysis was performed with parameterizing the flexural rigidity of the girder, span length, girder spacing, median strip, curbs. The influence of curbs and median strip would increase with lowering rigidity of girder. In addition, curbs lower the load distribution factor of exterior and interior girders.

• 기술사
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• 제16권4호
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• pp.4-14
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• 1983

when one is designing a continuous bridge with variable cross sections, it is very troublesome to integrate explicitly load terms and various factor under consideration so that it has different moment of inertia at each cross section. In this paper to obtain the influence line of a arbitary-span continuous beam with variable cross sections, the value of some particular function due to a load at any point can be carried out by numerical integration instead of definite integral. The ordinate of the influence line equals the product of the magnitude of the final moment at each support due to unit moment at any support and the load terms due to unit load, measured at the point of application of the load. It is concluded that this method can be easily used to design continuous bridges with arbitary cross sections.

• Advances in Computational Design
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• 제8권1호
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• pp.61-76
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• 2023

Fiber reinforced polymer (FRP) columns are increasingly being used in various engineering fields due to its high strength to weight ratio and corrosion resistance. Being a thin-walled structure, their designs are often governed by buckling.Buckling strength depends on state of stress of elements which is greatly influence by stacking sequence and various inaccuracies such as geometric imperfections and imperfections due to eccentricity of compressive load and non-uniform boundary conditions. In the present work, influence of load eccentricity on buckling strength of FRP column has been investigated by conducting parametric study. Numerical analyses were carried out by using finite element software ABAQUS. The finite element (FE) model was validated using experimental results from the literature, which demonstrated good agreement in terms of failure loads and deformed shapes.The influence of load eccentricity on buckling behavior is discussed with the help of developed graphs.

• 전산구조공학
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• 제3권1호
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• pp.109-116
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• 1990

본 연구에서는 사무실 적재하중을 체계적으로 조사.수집하여 등가등분하중을 산정하였다. 등가등분포하중은 슬래브, 보 기둥등의 부재별로 영향선을 이용하여 분석하였다. 여기에서 하중효과는 보와 슬래브에서는 휨모멘트, 기둥에서는 축력이 고려되었다. 산정된 등가등분포하중 자료로부터 적재하중의 확률적 특성과 영향면적과의 상관관계가 분석되었으며, 다른 하중조사결과와도 비교되었다. 분석된 적재하중의 확률모형을 이용하여 사용기간 동안의 극한값을 산정하였으며, 이 결과는 현행 설계적재하중과 비교되었다. 또한 보다 합리적인 설계적재하중을 결정할 수 있는 기초자료로서 영향면적에 따른 설게하중식을 제안하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1989년도 가을 학술발표회 논문집
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• pp.25-28
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• 1989

Live load data in domestic office buildings have been collected in a systematic manner. Based on surveyed data, equivalent uniformly distributed load intensities, which produce the same load effect as the actual spatially varying live load, have been obtained for various structural members(such as slab, beam, column, etc.). Influence surface method has been employed to compute load effects under real live load, inclucing beam moment, slab moment as well as axial force and moments in column. The results have been examined to find probabilistic characteristics and relationship between influence area and load intensity(or coefficient of variation). The results were also compared with other survey results and found to be reasonable.

• Smart Structures and Systems
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• 제32권6호
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• pp.371-382
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• 2023

Box girder bridges are now widely used in bridge construction, and it is necessary to perform load rating regularly to evaluate the load capacity of box girder bridges. Load testing is a common measure for load rating. However, the bridge must be loaded by many trucks under different loading conditions, which is time-consuming and laborious. To solve this problem, this paper proposes a load rating method for box girder bridges based on rapid moving loads testing. The method includes three steps. First, the quasi-influence factors of the bridge are obtained by crossing the bridge with rapidly moving loads, and the structural modal parameters are simultaneously obtained from the dynamic data to supplement. Second, an objective function is constructed, consisting of the quasi-influence factors at several measurement points and structural modal parameters. The finite element model for load rating is then updated based on the Rosenbrock method. Third, on this basis, a load rating method is proposed using the updated model. The load rating method proposed in this paper can considerably reduce the time duration of traditional static load testing and effectively utilize the dynamic and static properties of box girder bridges to obtain an accurate finite element model. The load capacity obtained based on the updated model can avoid the inconsistency of the evaluation results for the different structural members using the adjustment factors specified in codes.

• Earthquakes and Structures
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• 제11권4호
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• pp.609-627
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• 2016

Results of an experimental program are presented in this paper for the influence of vertical load on the in-plane behavior of masonry infilled steel frames. Five half-scaled single-story, single-bay steel frame specimens were tested under cyclic lateral loading. The specimens included four infilled frames and one bare frame. Two similar specimens as well as the bare frame had moment-resisting steel frames, while the remaining two specimens had pinned steel frames. For each frame type, one specimen was tested under simultaneous vertical and lateral loading, whereas the other was subjected only to lateral loading. The experimental results show that the vertical load changes the cracking patterns and failure modes of the infill panels. It improves dissipated hysteresis energy and equivalent viscous damping. Global responses of specimens, including stiffness and maximum strength, do no change by vertical loading considerably. Regarding the ductility, the presence of vertical load is ignorable in the specimen with moment-resisting frame. However, it increases the ductility of the infilled pinned frame specimen, leading to an enhancement in the m-factor by at least 2.5 times. In summary, it is concluded that the influence of the vertical load on the lateral response of infilled frames can be conservatively ignored.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.859-864
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• 2001

An effective live load model for analyzing probable maximum live load effects such as moment and shear in transverse direction was developed. The main procedure of this live load model is composed of four parts, i.e., firstly, determination of the appropriate influence lines in longitudinal direction, secondly, application of the characteristics of vehicles and traffic patterns in longitudinal direction, thirdly, determination of the appropriate influence lines in transverse direction, and fourthly, application of the characteristics of vehicles and traffic patterns in transverse direction. Through this procedure, the probabilistic distributions of maximum probable load effects are deduced in the form of probability density function (PDF) and/or cumulative density function(CDF). This live load model is able to consider local or global deterioration of bridges in the structural analysis.

• 한국정밀공학회지
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• 제9권1호
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• pp.126-136
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• 1992

In this paper, a simple structured feedback compensation scheme for a electro-hydraulic servo system to keep the response characteristics unchanged regardless of the load variation is proposed. In electro-hydraulic servo system, servovalve is most important control element. But the relation between input corrent and output flowrate of the servovalve has properties as follows; firstly, in spite of constant input current, output flowrate decreases as load pressure increases, secondly, according to frequency response of typical servovalve, the characteristics of gain and phase shift is something like 2'nd order system. Load pressure feedback compensation method has been applied to eliminate the first influence, the second influence has been improved by phase lead compensation method. As a result of above compensation methods, regardless of variation load condition, spring and inertia load, the compensation scheme has been verified to be effective within the range of frequency less than 25Hz by static response and dynamic response in time domain and frequency domain through experiments.